Notice that only the following characters
in the "upper halves"
are invariant
in the ISO Latin alphabets, in the sense of occurring in all of them
in the same code position:
no-break space,
soft hyphen,
and the characters § Ä ä Ö ö Ü ü É é ß.

Characters in upper halves of ISO Latin alphabets.
A table which lists the
Unicode
characters present in
at least one of the ISO Latin alphabets and their code
positions in them. Best viewed on a browser which supports Unicode,
but characters are specified by their Unicode code numbers too.

A combined mapping table from
ISO 8859 character sets to Unicode. This is plain text
and mostly useful for creating various programs like converters.
The structure is hopefully obvious:
each row begins with a
code position
m (in hexadecimal);
each column has a heading n; and table entry on row m,
column n specifies the
Unicode code value
of
the character which is in code position m in
ISO 8859-n. A value of 0000 indicates that
in ISO 8859-n,
no character is assigned to code position m.

There is an excellent
online character database by
Indrek Hein at the
Institute of the Estonian Language.
You can e.g. search for
Unicode characters by name or code position,
get lists of differences or conversion between some character sets
(such as the ISO 8859 family and many others),
and get lists of characters needed for different languages.